Mercury switch relay



Jl-llly- 24, 1934. c, J. WARNKE 1,967,954

MERCURY SWITCH RELAY Filed Feb. l. 1952 5 Shee'c'S-Slfleefl l July 24, 1934- c. J. WARNKE MERCURY SWITCH RELAY Filed Feb. l. 1932 3 Sheets-Sheet 2 July 24, 1934. c. J. wARNKE MERCURY SWITCH RELAY 3 Sheets-Sheet 5 Filed Feb. l. 19:5?.

comprisi:

li, (CH, Tte-375) invention relates to mercury switch relays and is directed more particularly to a device oi charact in which an auxiliary circuit may be utilized conjunction with a mercury switch, to interri1 main or load circuit.

@ne oi or my invention is to devise a relay a transformer and a mercury' switch in whicli. e secondary winding is included in an auxiliary cir uit which is conditioned to make or load circuit through the switch dependent upon the strength or the current in the auxiliary circuit.

A. further object is to provide a relay as indicated wherein the auxiliary circuit includes a transito-rincer secondary winding and an electrornagnet for controlling the load circuit making and. breaking positions of the mercury switch, the primary winding of the transformer being subject to a constant cyclic magnetization and the operativeness oi the electromagnet being dependent upon the strength of the magnetic eld surrounding the electromagnet which in turn is dependent upon whether an air gap exists in the auxiliary circuit, corresponding to an opening oi the latter.

A. further object is to devise a relay of the character indicated employing a mercury switch having a container which is maintained in an immobile state at all times, but is provided with a movable part which acts in response to predetermined conditions for the purpose of making and breaking the circuit through the switch.

A further object is to provide a relay in which the movable part is formed of magnetic material and is utilized as the core of a solenoid, the presence of current passing through the solenoid,fwhich is series connected with the secondary winding of the transformer, determining the position of the movable part which corresponds to a circuit breaking position of the mercury switch, and the cessation of said current upon an interruption of the solenoid circuit permitting the part to fall under the action of gravity to complete the load' circuit through the switch.

A further object is to devise a relay of the character indicated in which the auxiliary circuit is capable of being placed in an operative condition by relatively feeble currents, such as those which may be made available by thermopjles, the smis radiation, photo-electric cells, grid glow vacuum valves, and devices in general which are capacitated for the production of feeble currents only. se that the relay may be 1ocated in an environment-in which feeble currents esi ai .l are e La il u l., u s ai by direct The d; "Til a corporation No. gitiliid only available without affecting in any mannei e capacity for adequate operation.

l urther object is to devise a relay which is particularly adaptable for use under conditions requiring an indication of a change in temperature, such as ovens, furnaces, mechanical reirigerators, and the like, wherein variations in temperature affect the operation ci other apparatos, and also under conditions where it is desired to operate certain apparatus at definite time intein/als.

A further object is to provide a mercury switch relay emploi/inge modied ironclad solenoid type of electromagnet which is arranged to materially lessen the iron losses due to eddy currents, so that the relay is characterized by a high degree of sensitiveness, promptness of action and holding power. y

A further object is the provision oi a. relay which is featured by a. ruggedness in construction, long life, positive, efficient and dependable operation, and in whichA the composing materials arelsuch as to substantially improve the operating characteristics of the switch relay relative to results now obtainable with devices oi this type in common use.

My invention is primarily intended as an arrangement comprising a transformer and a mercury switch which may be so conditioned and arranged in a load circuit that the latter itself furnishes the energy required for its interruption, dependent upon conditions extraneous of the circuit. According to the present disclosure, the primary winding of the transformer is constantly energized, While the secondary Winding is connected in series with an electromagnet that controls the circuit making or breaking positions of the mercury switch and also irl-series with some form of switch means, generically considered, whether of an electric or a mechanical type. As long as the auxiliary circuit, consisting of the secondary winding and its associated elements, is broken at the switch means, a current will not be induced in the secondary winding so that the electromagnet will be unable to effect any operation of the mercury switch. However, promptly upon a closing of the switch means, the magnetic eld established around the electromagnet by the induced current enables the latter to effect the desired operation. The relay may therefore be regarded as embodying in some respects power boosting characteristics which become available merely by a closing of the auxiliary circuit, the energy for the magnetic eld, however, being completely supplied by the main or load circuit.

lit

The relay is therefore peculiarly adapted for use under conditions which are characterized by a delicacy of control and a relatively small amount of energy available for effecting the primary operation of the relay.

These and further objects of my invention will be set forth in the following speciication, reference being had tothe accompanying drawings,v

and the novel meansv by which said objects are electuated will be definitely pointed out in the claim.

In the drawings:

Figure 1 is an elevation of the relay as it appears in its enclosing casing, the cover of the latter having been removed.

Fig. 2 is a section along the line 2--2 in Fig. l, looking in the direction of the arrows, the cover being in position.

Fig. 3 is a side, sectional elevation of the relay, as viewed along the line 3--3 in Fig. l, looking in the direction of the arrows.

Fig. 4 is a sectional elevation of the mercury switch portion of the relay and its associated solenoid and laminated yoke, the switch being viewed as it appears in Fig. 3.

Fig. 5 is a vertical, sectional elevation, somewhat enlarged, of the mercury switch container, the sleeve which functions as a core for the solenoid coil being shown in an elevated position, or one which it would occupy when the solenoid'coil is energized.

Fig. 6 is a diagrammatic illustration, partly in section, of the mercury switch container, and its associated laminated yoke and solenoid coil, the parts being somewhat enlarged and viewed from the opposite side Vof the device as shown in Fig. 4. ,V

Fig. 7 is a diagrammatic illustration, the mercury switch being partly shown in section, showing the electrical connections of the relay.

Fig. 8 is also a diagrammatic illustration showing a modified circuit arrangement with which the relay may be utilized. f

Referring to Fig. 5 of the drawings, the numeral 10 designates the container of the mercury switch portion of the relay, the same being generally elongated in shape and preferably composed of a glass that is characterized by a comparatively high melting point and a low coefficient of thermal expansion relative to the lamp glass now used in the industry and which is therefore capable o f withstanding the ravages of the electric arc when such occurs within the container upon the completion or breaking of the circuit. In the present instance, magnesium silicate glass has been found suitable for this purpose in that' it is substantially void of those materials, such as lead, tin, antimony, and substances generally which are decomposed under and by the action of the electric arc and are picked up by or amalgamated with the 'mercury to thereby lessen its original state of purification and capacity for effective operation in the switch. Glass of the indicated type in addition possesses high tensile strength, andsuflicient elasticity towithstand and be substantially unaffected by rapid temperature fluctuations over wide ranges. It will be understood. however, that the indication of magnesium silicate glass being preferred for the material of which the container 10 is composed is not to be considered as restrictive in nature, for the essential elements of thel present invention reside in otherl features and combinations 'The' container -10' is'provided with a lower und Leonesa wall l1 and is pinch-sealed at the .opposite end, as at 12, in the customary manner. Prior to being sealed, it is contemplated that the interior thereof will be exhausted in accordance with standard practice, subsequent to the insertion of the parts presently described, and afterwards nlled with one of the gases which are usually em-` ployed for the purpose of substantially suppressing the electric arc which tends to form when a circuit is made or broken in the switch, improving the heat conducting characteristics within thecontainer, protecting the metallic electrodes from deterioration arising from ionization or from whatever cause, arresting the wetting or amalgamation of the electrodes by the mercury, and of keeping the electrode surfaces clean at all times. 1n the present instance, preformed helium hydride gas has been found entirely satisfactory for the'indicated purpose, as in addition to incorporationg the foregoing properties, it is also characterized by extreme stability and thus is particularly resistant to combination with most materials. However, as in the case of the material composing the container 10, I do not desire to be restricted by the foregoing suggestions as to the use of a gas fill, as other gases may be found entirely desirable and in'view of the fact that the present invention is more particularly directed towards other features of construction.

Extending through 'the end wall 1l are leadin wires 13 and 14, the material composing said wires being preferably that which is usually employed for the indicated purpose, such as dumet wire and. the like, and the character of the seal between these lead-in wires and the glass container being such as to prevent leakage at the 10. Within said container, an electrode l5 issuitably connected to the lead-in wire 13 and projects only slightly above the inner surface of the wall 11. A glass insulating sleeve 16 is fused at one end to the wall 11 and the lead-in wire 14 extends upwardly therethrough for attachment to an electrode 17 which is disposed at a predetermined distance above the electrode l5 fora purpose presently explained. The precise materials of which the electrodes 15 and 17 are composed form no part of the present invention, since standard practice may be adopted in this respect, although itis contemplated that..in any case, the material selected will be such as to oler resistance to the erosive e'ects of the electric arc.

A mass of mercury 18 is placedin the container y 10 to rest against the lower wall thereof and to be -20 exists between the adjacent surfaces of the container and plunger. Thelatter is further provided with a passage 21 which extends completely through the plunger in order to provide clearance for the sleeve 16 and the passage of mercury upwardly therethrough in the manner presently closing of the switch means 57, the solenoid coil 23 is immediately energized and pulls the plunger to the position shown in Fig. 5, or one in which the surface oi the mercury pool ld falls to a level below the electrode 17, thus breaking the main circuit. The foregoing condition will be maintained so long as the switch means 57 remains closed, but promptly upon an opening thereof, the initial condition will obtain, namely, a. cessation of the magnetic field surrounding the solenoid coil 23, so that the plunger i9 will drop under the action of gravity into the 'position shown in Fig. 7, thus raising the level of the mercury pool into contact with the electrode i7 and again com= pleting the load circuit.

In the modied circuit arrangement shown in Fig. t, the input terminal i5 is not connected to the output terminal 47, but both input terminals are connected to the primary Winding 34 in the manner alcove described and said terminals con.-v

nected to a suitable electric circuit which is independent of the circuit that is connected to the terminals 47 and d8. In the present instance, the

' teral i7 is connected to the lead-in wire la nacneac t .iected to a constant cyclic magnetization `from that circuit which is connected to the terminals 4:5 and 46 in the manner above described, but the indicated circuit is wholly ,independent of that circuit which is connected to the terminals 47 and d8. Upon a closing`of the switch means 57, as stated above, the plunger 19 is Withdrawn to interrupt the electric circuit through the terminals 47 and a8, while a contrary condition is established when the switch means 57 is open.

While ll have shown one set of elements and combinations thereof for eiectuating my improved relay, it Will be understood that the same is intended for purpose of illustration only and in no wise to restrict, the device to the rexact forms and structures shown, for many changes may he made therein Without departing from the spirit of my invention.

l claim:

.lin a relay, a casing, a transformer in the cas- -ing including a secondary coil, a vertically disposed switch operating coil in series with the secondary coil, and a mercury switch associated with the operating coil and comprising a switch envelope, spaced electrodes in the envelope, a quantity of mercury in the envelope adapted to maire or break an electrical circuit through the electrodes according to its level, a displacer for determining the mercury level, said displacer being responsive .to said secondary coil. l

CARL JT. WARNKE, 

